Surgical suture needle

ABSTRACT

A surgical needle is disclosed and includes an elongated needle body defining a longitudinal axis The surgical needle has a first end for attachment to a suture and a second needled end for penetrating tissue. The needled end includes lower and upper opposed surfaces and a pair of side surfaces extending between the lower and upper surfaces and being contiguous therewith. The upper surface and side surfaces extend to a pointed tip. The lower surface extends to a cutting edge, which is defined at the intersection of the side surfaces and proximal of the pointed tip. The cutting edge extends in oblique relation relative to the longitudinal axis and terminates at the pointed tip.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of and claims the benefits of andpriority to U.S. patent application Ser. No. 10,618,994, which was filedon Jul. 14, 2003, now U.S. Pat. No. 7,655,024. The entire contents ofwhich are incorporated herein by reference.

BACKGROUND

1. Technical Field

The present disclosure relates to a surgical suturing needle forsuturing cutaneous and subcutaneous tissue, and in particular, relatesto a surgical needle having a multifaceted penetrating needle endcharacterized by enhanced penetrability and needle hardness.

2. Background of Related Art

Suturing needles for applying sutures, or stitches, by hand in cutaneousand subcutaneous tissue are well known in the art. Typically, thesuturing needles are used to close wounds or adjoin adjacent tissue,often at the conclusion of a surgical procedure. Suturing needles areusually made from a cut blank of material such as stainless steel. Thecut blank is metal-worked using well known machining techniques to formthe suturing needle. The needle generally includes a shaft, a rear endportion with an aperture or channel to secure a suture thread and aneedle head at a front end portion for puncturing skin and passingthrough tissue. The needle head typically incorporates a sharpenedneedle tip at its distal end and cutting edges. Alternatively, theneedle tip may be of a tapered configuration. Straight and curvedneedles including multiple curved configurations are also known in theart.

An important consideration in the design of surgical suturing needles isneedle sharpness. Sharper needles require less force to penetrate tissueand thus cause less tissue trauma. In addition, a sharper needle reducesfatigue on the needle itself, making it less likely to bend or breakduring suturing. Needle sharpness is typically defined in terms of“penetration force”—the force necessary for a needle to puncture, orpenetrate, the tissue. The penetration force is primarily determined bythe design and sharpness of the needle point and the cutting edgesformed on the needle head. Needle sharpness is also affected by dragforce on the needle as it travels through the tissue. The drag forcealso depends upon the design and sharpness of the needle, and thepresence of a lubricating coating.

Another important consideration in needle design and manufacture is tomaximize resistance to bending or breakage during use. The strength of asuturing needle is a measure of its ability to resist bending and isdetermined by such factors as (a) the material of fabrication, (b) thecross-sectional shape of the needle, and (c) the heat treatment appliedto the needle during manufacturing. Needle strength should be balancedby needle ductility, which is defined in terms of the ability of theneedle to be reshaped after it flexes from its original shape. Asurgical needle with good strength characteristics but little or noductility can be brittle, and may snap and break during use. It isgenerally known that in working with a metallic material, as thestrength of the material increases the ductility will decrease.Therefore, it is desirable to carefully balance the strength andductility characteristics of a suturing needle.

SUMMARY

Accordingly, the present disclosure is directed to further advancementsin surgical suturing needles. The surgical needle of the presentdisclosure possesses enhanced needle attributes including needlesharpness and resistance to bending or breaking during use. In oneembodiment, the surgical needle includes an elongated needle bodydefining a longitudinal y axis and x and z axes transverse to the yaxis. The elongated needle body includes a central shaft, a first endfor attachment to a suture and a second needled end for penetratingtissue. The needled end includes lower and upper opposed, preferably,planar surfaces and a pair of side surfaces extending between the lowerand upper surfaces and contiguous therewith. The upper surface and sidesurfaces extend to a pointed tip. The lower surface extends to a cuttingedge defined at the intersection of the side surfaces and proximal ofthe pointed tip. The cutting edge extends in oblique relation relativeto the longitudinal axis of the needle body and terminates at thepointed tip. The linear cutting edge intersects the upper surface at anangle ranging from about 15° to about 30° relative to the longitudinalaxis.

In the preferred embodiment, the needle end defines a first transversecross-sectional dimension adjacent the central shaft, and having ageneral trapezoidal configuration. The needle end also defines a secondtransverse cross-sectional dimension adjacent the pointed tip, andhaving a general triangular configuration. The first cross-sectionaldimension may define a dimension along the z-axes corresponding to afirst width of the needle end with the first width being at least equalto, preferably, greater than, a corresponding shaft width of the centralshaft. The first cross-sectional dimension defines a dimension along thex-axis corresponding to a first height of the needle end with the firstheight being less than a corresponding shaft height of the centralshaft.

The needle body may be curved along the longitudinal axis, preferably,defining an angle of curvature ranging from about 80° to about 180° .Alternatively, the needle body may be straight.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the disclosureand, together with a general description of the disclosure given above,and the detailed description of the embodiment(s) given below, serve toexplain the principles of the disclosure.

FIG. 1 is a side elevational view of the surgical needle in accordancewith the principles of the present disclosure;

FIG. 2 is a cross-sectional view of the central shaft of the surgicalneedle taken along the lines 2-2 of FIG. 1;

FIG. 3 is an enlarged plan view of the suture end of the surgical needletaken along the lines 3-3 of FIG. 1;

FIG. 4 is an axial view of the suture end of the surgical needle takenalong the lines 4-4 of FIG. 3;

FIG. 5 is a top plan view of the penetrating needle end of the surgicalneedle taken along the lines 5-5 of FIG. 1;

FIG. 6 is a cross-sectional view of the needle end taken along the lines6-6 of FIG. 5; and

FIG. 7 is a cross-sectional view of the needle end taken along the lines7-7 of FIG. 5.

BRIEF DESCRIPTION OF PREFERRED EMBODIMENTS

Preferred embodiment(s) of the surgical needle of the present disclosurewill now be described in detail with reference to the drawings whereinlike reference numerals identify similar or like elements throughout theseveral views. As used herein, the term “distal” refers to that portionwhich is further from the user, while the term “proximal” refers to thatportion which is closest to the user.

With reference now to FIG. 1, the surgical needle 10 of the presentdisclosure is illustrated. Surgical needle 10 includes elongated needlebody 12 having first or proximal end 14 and second or distal needled end16. Needle body 12 is curved along its length through an arc “G” rangingfrom about 90° to about 180°. Other angles of curvature are alsoenvisioned. It is also contemplated that needle body 12 may be straight.As depicted in FIG. 2, needle body 12 defines longitudinal axis “y”which extends along the length of needle body 12 and transverse axes “x”and “z”. Transverse axes “x” and “z” correspond to the height and widthdimensions of needle body 12, respectively.

With continued reference to FIGS. 1 and 2, needle body 12 definescentral shaft 18 which is preferably rectangular in cross-sectiondefining a height “H” (corresponding to an x-dimension) and a width “W”(corresponding to a z-dimension) as best depicted in FIG. 2. The ratioof the dimensions of the height “H” to width “W”, i.e., “H”/“W” ispreferably less than 1.1/1, preferably about 1.06/1 although otherratios are also contemplated. Although a greater “H”/“W” ratio (i.e., amore pronounced rectangular cross-section) may increase the strength ofcentral shaft 18, the reduced ratio of 1.1/1 or less is more desirable.Specifically, the cross-section of central shaft 18 is easier to handleby the surgeon and may be more easily manipulated by a needle holder,e.g., needle forceps. Central shaft 18 may also be square incross-section or alternatively rounded.

With reference now to FIGS. 3 and 4, in conjunction with FIG. 1, firstend 14 defines an open U-shaped channel 20 dimensioned for reception ofa suture end of a suture. U-shaped channel 20 is closed about the sutureend through conventional swaging or crimping processes to secure thesuture to elongated needle body 12. The dimensioning of U-shaped channel20 of first end 14 may be selected to provide for permanent(non-detachable) or detachable securement of the suture to needle body12. The type of securement effectuated is also dependent upon theswaging force employed during the attachment process. It is furtherenvisioned that first end 14 may be provided with an enclosed bore oraperture formed through, e.g., a laser drilling process, for receptionof the suture end. Adhesive suture attachment methodologies are alsoenvisioned.

Referring now to FIGS. 5-7, in view of FIG. 1, needled end 16 will bediscussed in detail. Needled end 16 includes enlarged needle head 22which is advantageously dimensioned to reduce the penetration forcerequired to penetrate tissue while optimizing needle strength.Specifically, needle head 22 includes first and second surfaces 24, 26(which will be referred to hereinafter as upper and lower surfaces 24,26 for descriptive purposes) and side surfaces 28 which interconnect theupper and lower surfaces 24, 26. Side surfaces 28 intersect at linearcutting edge 30 which terminates at needle point 32. Upper and lowersurfaces 24, 26 are preferably planar and in substantial parallelrelation to the each other. Upper surface 24 extends to, and iscoterminous with, needle point 32 while lower surface 26 terminates atthe beginning of cutting edge 30. Side surfaces 28 commence at centralshaft 18 and extend to intersect along cutting edge 30. The dimension orwidth of each side surfaces 28 decreases from needle point 32 togradually transition into central shaft 18 of needle body 12.

As appreciated, by virtue of the configuration of needle head 22, threeprimary cutting edges for penetrating tissue are provided. Two primarycutting edges 34 are defined along the intersection of side surfaces 28and upper surface 24, and the remaining primary cutting edge is thelinear cutting edge 30 defined at the juncture of the two side surfaces28.

As depicted in FIGS. 6 and 7, needle head 22 provides a multiplecross-sectional configuration. The cross-section along a firstintermediate portion of needle head 22 (FIG. 6) defines a generalnarrowed trapezoidal configuration. The height “ST” at this location ispreferably no greater than about 50% (or one-half) of the correspondingheight “H” of central shaft 18, most preferably, no greater than about45% of the height “H”. The maximum width “SW” at this location is noless than 1.0 times the corresponding width “W” of central shaft 18. Inone preferred embodiment, the maximum width “SW” is no less than 1.5times the width “W” of the central shaft 18. Accordingly, needle head 22at this location provides a reduced profile or cross-sectional dimensionwhich significantly facilitates passage of the needle head 22 throughtissue. In addition, the pronounced height to width (“H”/“W”) ratiosubstantially increases the overall strength of needle head 22. Theincluded angle “B” defined at the intersection of side surfaces 28 andupper surface 24 is sufficiently large to avoid the potential of needlebreakage at this location. The preferred angle “B” ranges from about 35°to about 55°.

The cross-sectional configuration of needle head 22 adjacent needlepoint 32 is triangular having the three cutting edges 30, 34 in generalclose proximity to define a narrowed sharp needle end to facilitatepenetration through the tissue. The preferred included angle “d”(FIG. 1) defined at the intersection of linear cutting edge 30 and uppersurface 24 is preferably between about 15° and about 30°.

The surgical suturing needle of the present disclosure possessesattributes of primary significance in suturing needles. Specifically, byvirtue of the multiple cross-sectional character of needle 10, theneedle possesses superior needle sharpness and also demonstratessuperior strength. In particular, the narrowed triangularcross-sectional dimension of the needle head 22 adjacent the needlepoint 32 with its closely positioned cutting edges 30, 34 produces asharpened profile which significantly reduces the penetration forcerequired to penetrate the body tissue. Moreover, the cutting edges 34extend to the widest part of needle head 22 thereby slicing, inconjunction with linear cutting edge 30, the tissue as it passes throughand providing an opening which is slightly larger than the cross-sectionof central shaft 18, consequently, significantly reducing the drag forceand permitting the shaft 18 to easily pass through the tissue. Theflattened trapezoidal cross-section of the needle head 22 also producesa profile conducive to continued passage of the needle head 22 throughthe tissue.

The choice of materials of surgical needle 10 is made to optimizestrength, ductility and resistance to bending or breaking of the needle.However, as noted, the cross-sectional shape and dimensions of theneedle contributes significantly to the physical characteristics of theneedle. Preferred materials include stainless steel such as series “300”stainless steels, which typically have tensile strengths of between325,000-350,000 lbs/in.sup.2, attain their high strength from undergoingcold working as the material is converted from an ingot to wire of thedesired diameter.

Surgical needle 10 is manufactured through conventional cutting,coining, grinding and/or swaging processes, and may be heat treated tofurther enhance its strength and resistance to bending.

It will be understood that various modifications may be made to theembodiments disclosed herein. Therefore, the above description shouldnot be construed as limiting, but merely as exemplifications ofpreferred embodiments. Those skilled in the art will envision othermodifications within the scope and spirit of the claims appended hereto.

1. A surgical needle, which comprises: an elongated needle body defining a longitudinal y axis and x and z axes transverse to the y axis, the elongated needle body including a central shaft and having a first end for attachment to a suture and a second needle end for penetrating tissue, the second needle end having a transition area, a proximal portion of the second needle end disposed proximally of the transition area including a first length having a trapezoidal transverse cross-section and a distal portion of the second needle end disposed distally of the transition area including a second length having a triangular transverse cross-section, the first length being longer than the second length.
 2. The surgical needle according to claim 1 wherein the trapezoidal cross-sectional dimension defines a dimension along the z-axes corresponding to a first width of the second needle end, the first width at least equal to a corresponding shaft width of the central shaft.
 3. The surgical needle according to claim 2 wherein the first width is greater than a corresponding shaft width of the central shaft.
 4. The surgical needle according to claim 3 wherein the first width is not less than about 1.5 times the shaft width.
 5. The surgical needle according to claim 1 wherein the trapezoidal cross-sectional dimension defines a dimension along the x-axis corresponding to a first height of the second needle end, the first height being less than a corresponding shaft height of the central shaft.
 6. The surgical needle according to claim 5 wherein the first height is not greater than about 0.5 times the shaft height.
 7. The surgical needle according to claim 1 wherein the needle body is curved along the longitudinal y axis.
 8. The surgical needle according to claim 7 wherein the needle body defines an angle of curvature ranging from about 80° to about 180°.
 9. The surgical needle according to claim 1 wherein the second needle end defines a maximum dimension along the z-axis greater than a corresponding maximum dimension along the z-axis of the central shaft.
 10. A surgical needle, which comprises: an elongated needle body defining a longitudinal y axis, the elongated needle body including a central shaft and having a first end for attachment to a suture and a second needle end for penetrating tissue, the second needle end having a transition area, a proximal portion of the second needle end disposed proximally of the transition area including a first length having a trapezoidal transverse cross-sectional dimension, and a distal portion of the second needle end disposed distally of the transition area including a second length having a triangular transverse cross-sectional dimension, the first length being longer than the second length, at least a portion of the first length having an area that decreases distally towards the second needle end, and at least a portion of the first length having an area that decreases proximally towards the central shaft of the needle body.
 11. The surgical needle according to claim 10 wherein a maximum dimension of the second needle end is at least about 1.5 times a maximum dimension of the central shaft.
 12. The surgical needle according to claim 10 wherein the trapezoidal cross-sectional dimension defines a dimension along a z-axes corresponding to a first width of the second needle end, the first width at least equal to a corresponding shaft width of the central shaft.
 13. The surgical needle according to claim 12 wherein the first width is greater than a corresponding shaft width of the central shaft.
 14. The surgical needle according to claim 13 wherein the first width is not less than about 1.5 times the shaft width.
 15. The surgical needle according to claim 10 wherein the trapezoidal cross-sectional dimension defines a dimension along an x-axis corresponding to a first height of the second needle end, the first height being less than a corresponding shaft height of the central shaft.
 16. The surgical needle according to claim 15 wherein the first height is not greater than about 0.5 times the shaft height.
 17. The surgical needle according to claim 10 wherein the needle body is curved along the longitudinal y axis.
 18. The surgical needle according to claim 17 wherein the needle body defines an angle of curvature ranging from about 80° to about 180°.
 19. The surgical needle according to claim 10 wherein the second needle end defines a maximum dimension along a z-axis greater than a corresponding maximum dimension along the z-axis of the central shaft. 